Commit 587b9bfe authored by Dmitry Osipenko's avatar Dmitry Osipenko Committed by Rafael J. Wysocki
Browse files

kernel/reboot: Use static handler for register_platform_power_off() 



The register_platform_power_off() fails on m68k platform due to the
memory allocation error that happens at a very early boot time when
memory allocator isn't available yet. Fix it by using a static sys-off
handler for the platform-level power-off handlers.

Fixes: f0f7e526 ("m68k: Switch to new sys-off handler API")
Reported-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: default avatarDmitry Osipenko <dmitry.osipenko@collabora.com>
Reviewed-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Tested-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 1ff7bc3b

kernel/reboot.c

+37 −6
Original line number Diff line number Diff line
@@ -315,6 +315,37 @@ static int sys_off_notify(struct notifier_block *nb, 
	return handler->sys_off_cb(&data);

}



static struct sys_off_handler platform_sys_off_handler;



static struct sys_off_handler *alloc_sys_off_handler(int priority)

{

	struct sys_off_handler *handler;



	/*

	 * Platforms like m68k can't allocate sys_off handler dynamically

	 * at the early boot time because memory allocator isn't available yet.

	 */

	if (priority == SYS_OFF_PRIO_PLATFORM) {

		handler = &platform_sys_off_handler;

		if (handler->cb_data)

			return ERR_PTR(-EBUSY);

	} else {

		handler = kzalloc(sizeof(*handler), GFP_KERNEL);

		if (!handler)

			return ERR_PTR(-ENOMEM);

	}



	return handler;

}



static void free_sys_off_handler(struct sys_off_handler *handler)

{

	if (handler == &platform_sys_off_handler)

		memset(handler, 0, sizeof(*handler));

	else

		kfree(handler);

}



/**

 *	register_sys_off_handler - Register sys-off handler

 *	@mode: Sys-off mode
@@ -345,9 +376,9 @@ register_sys_off_handler(enum sys_off_mode mode, 
	struct sys_off_handler *handler;

	int err;



	handler = kzalloc(sizeof(*handler), GFP_KERNEL);

	if (!handler)

		return ERR_PTR(-ENOMEM);

	handler = alloc_sys_off_handler(priority);

	if (IS_ERR(handler))

		return handler;



	switch (mode) {

	case SYS_OFF_MODE_POWER_OFF_PREPARE:
@@ -364,7 +395,7 @@ register_sys_off_handler(enum sys_off_mode mode, 
		break;



	default:

		kfree(handler);

		free_sys_off_handler(handler);

		return ERR_PTR(-EINVAL);

	}
@@ -391,7 +422,7 @@ register_sys_off_handler(enum sys_off_mode mode, 
	}



	if (err) {

		kfree(handler);

		free_sys_off_handler(handler);

		return ERR_PTR(err);

	}
@@ -422,7 +453,7 @@ void unregister_sys_off_handler(struct sys_off_handler *handler) 
	/* sanity check, shall never happen */

	WARN_ON(err);



	kfree(handler);

	free_sys_off_handler(handler);

}

EXPORT_SYMBOL_GPL(unregister_sys_off_handler);